Horizon 1 1 17 ACL : Articles dans des revues avec comité de lecture répertoriées par l'AERES Proceedings of the National Academy of Sciences of the United States of America E1343-E1352 AIDS HIV-1 gorilla SIVgor zoonotic transmission CAMEROUN GABON OUGANDA REPUBLIQUE DEMOCRATIQUE DU CONGO 2015 fdi:010064059 ENG Proceedings of the National Academy of Sciences of the United States of America 0027-8424 ISI:000351060000024 11 10.1073/pnas.1502022112 https://www.documentation.ird.fr/hor/fdi:010064059 https://www.documentation.ird.fr/intranet/publi/2015/04/010064059.pdf 112 Horizon (IRD) HIV-1, the cause of AIDS, is composed of four phylogenetic lineages, groups M, N, O, and P, each of which resulted from an independent cross-species transmission event of simian immunodeficiency viruses (SIVs) infecting African apes. Although groups M and N have been traced to geographically distinct chimpanzee communities in southern Cameroon, the reservoirs of groups O and P remain unknown. Here, we screened fecal samples fromwestern lowland (n = 2,611), eastern lowland (n = 103), and mountain (n = 218) gorillas for gorilla SIV (SIVgor) antibodies and nucleic acids. Despite testing wild troops throughout southern Cameroon (n = 14), northern Gabon (n = 16), the Democratic Republic of Congo (n = 2), and Uganda (n = 1), SIVgor was identified at only four sites in southern Cameroon, with prevalences ranging from 0.8-22%. Amplification of partial and full-length SIVgor sequences revealed extensive genetic diversity, but all SIVgor strains were derived from a single lineage within the chimpanzee SIV (SIVcpz) radiation. Two fully sequenced gorilla viruses from southwestern Cameroon were very closely related to, and likely represent the source population of, HIV-1 group P. Most of the genome of a third SIVgor strain, from central Cameroon, was very closely related to HIV-1 group O, again pointing to gorillas as the immediate source. Functional analyses identified the cytidine deaminase APOBEC3G as a barrier for chimpanzee-to-gorilla, but not gorilla-to-human, virus transmission. These data indicate that HIV-1 group O, which spreads epidemically in west central Africa and is estimated to have infected around 100,000 people, originated by cross-species transmission from western lowland gorillas. 052 ; 080 UR233 Gabon / Rwanda